Sewing-machine



F. ZALESKI.

SEWING MACHINE.

APPLlcAHoN FILED MAY1s,191a.

1,838,848. Patented'Apr. 27, 1920.

4 SHEETS-SHEET I.

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` Frank ZuleSKi WMMQMJ ff Atys.

F. ZALESKI.

SEWING MACHINE.

APPucATloN FILED MAY13, |918.

Patented Apr. 27, 1920.

4 SHEETS-SHEET 2.

FfunK Zc1\eSK 67 68 Anys.

F. ZALESKI.

SEWING MACHINE.

APPLICATlON FILED MAY I3, I9I8.

Patented Apr. 27, 1920.

4 SHEETS-SHEET s.

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SEWING MACHINE.

APPLxcATloN mio MAYIB. 19m.

Patented Apr. 27,1920.

4 SHEETS-SHEET 4.

FTcmK ZulesKi by @am Mal/W Anya eration and t en to FRANK ZALESKI, 0FBOSTON, MASSACHUSETTS, ASSIGNOR TO THE REECE BUTTON HOLE MACHINE`COMPANY, OF BOSTON, MASSACHUSETTS, A 'CORPORATION OF MAINE.

SEWING-MACHINE.

Specification of Letters Patent.

i Patented Apr. 27, 1920.

Original application filed DecemberS, 1917, Serial No. 206,215. 4Dividedand this application led May 13,

- 1918. Serial No. 234,047.

To all whom t mag/concern:

Be' it known that I, FRANK ZAL'ESKI, a

subject of the Emperor of Germany, residing accompanying drawing, is aspecification,

like characters on the drawing representing'l like parts. v

This invention relates to sewing machines of that type which are`provided with upper-thread-handling mechanism and under thread-handlingmechanism and are adapted tol perform a predetermined stitching opbeautomatically brought to rest. As an example of sewing machines wouldrefer to buttonhole sewthat are adapted when set inI form the overseamstitches on operation to to be brought-torest a buttonhole and thenautomatically at the completion of the but-v tonhole. Some sewingmachines, of this type are provided with means end of the-stitchingoperation; and the present invention relates particularly to a sewingmachine of thistype.

The upper-thread-handlingmechanism usually comprises an eye-pointedneedle by which the upper thread is manipulated, and theunder-thread-handling mechanism includes alooper arranged to take theloops of upper thread as they are inserted through the work by theupperneedle and an under needle for inserting through the loops of upperthread.

Sewing machines of this type are usually constructed and arrangediso'that when they are brought to rest at the end of each seam or stitchingoperation, the upper needle is in raised position and the upper threadfrom .the upper needle extends through the work and around the looper ofthe under-thread-y handling mechanism. Hence' on the under side of thework there will be found not only the under thread leading from the workto ltion of the looper during the last stitchbut also the loop of thesource of supply,

work

upper thread which extends from the under the looper and back throughthe workagain to the upper needle.

If a sewing machine of this type 'is provided with threadtrimmingmechanism for trimmingthe under thread close to the work of which thefolwhich is apt yhandling mechanism, and

for. cutting the under thread beneath the work at1 the 'operate loops ofunder thread at theend of 'the stitching operation, such thread-trimmingmechanism will operate to cut not only the under thread, but also theloop of upper thread which is held by the looper. This cutting of theloop of upper thread to drop intd the under-threadafter the machine hasbeen in operation for a considerable time there will be quiteanaccumulation of such thread ends which are apt to clog up or in-4terfere .with the operations o'f the underthread-handling mechanism.

The object ofthe present provide a construction by which the productionof these thread ends will be prevented and I accomplish thisv hereinby means which becomes operative during the forming of the last stitchto prevent the looper from will produce a. short length of threadinvention is to engaging the loopof upperA thread so that when. thesewing machine is brou ht to rest with the needle raised there will Feno loop of upper thread held by the looper and the thread-trimmingmechanism, therefore, will only on the under thread.

In order to give an understanding of my invention, I have illustrated inthe drawings a'selected embodiment thereof' which will now be described,after which the novel features will be pointed out in the appendedclaims.

In the drawings, `Figure 1 isa side'view of a sewing machine embodyingmy invention;

Fig. 2 is a plan view of the driving and stopping mechanism therefor;

Fig. 3 is a plan view ofthe work-holding means;

Fig. 4 is a fragmentaryl View showing the thread-trimming device;

Fig. 5 is a view of theunder-threadhandling mechanism;

Fig. 6 is a' top plan view of the underthread-handling mechanism; V

Fig. 7 is a fragmentary view showing the normal operation of the looper;

'Figs 8 and 9 are views showing the operaforming' movement;

Fig. 10 is a section on holel sewing vmachine of the well-known Reecetype, an example of which may be found in United States Letters PatentNo. 1,188,942, dated June 27, 1916. This sewing machine compriseswork-holding means by which the Work is held and stitch-formingmechanism for producing the buttonhole stitches. The Work-holding meansis in the form of a clamp plate l which is slidably mounted upon the bedplate 2 of the sewing machine frame and Work clamps 3 carried by arms 4pivoted to the clamp plate and which are movable toward and from theclamp plate for clamping theV Work w 'and releasing it.

The stitch-formin mechanism comprises upper thread-handling mechanism inthe form of an eye-pointed needle 5 carried by the needle bar 6 which ismounted for vertical reciprocation in the head or overhanging arm 7 ofthe frame, and an under-threadhandling mechanism which is mounted/on arotary turret 8 and which comprises an under or lower oscillating needle9 and aI looper 1,0. The turret 8 is mounted for rotation in suitablebearings 11 carried by the depending portion 12 of the frame, and it iis provided at its upper end with a throatplate 13 having an opening 99through which the upper and under needles operate. The requiredmovements of the under needle 9 and looper 10 are secured from a'spindle20 which is mounted in the turret for vertical reciprocation. i f

The looper 10 is secured'toy a block 79 pivoted at 91 to the turret 8,said block having a cam slot 78 therein in which cperatesa roll 77carried by the spindle 20. Ther vertical movements of the spindle thusoperate through the cam slot to oscillate the block 79 and the looper10. -The spindle is connected at its lower end to a'rocking lever 21pivotally mounted at 2,2, therear end of said lever having a link 23connected thereto which is actuated from an eccentric on the drivingshaft 24 of the stitch-forming mechanism..

The turret has a pinion 14 rigid thereWit which meshes With a segmentalgear 15 carried by a rockshaft 16, and the needle bar 6 also has apinion 17 thereon which meshes with a segmental gear 18 carried by vtherock-shaft 16. The rock-shaft 16 is oper- :ated at the proper time froma main cam 19 so as to turn the turret and upper needle during thestitching around the ends of the buttonhole. The work-holding means andthe stitch-forming mechanism are ar ranged to have a movement relativeto each other, and in the machine herein shown, this movement isprovided for by making the Work-holding means capable of reciprocat-Aing movement on the bed plate, such reciprocating movement being derivedfrom the feed cam 19 by any suitable means usually7 employed inbuttonhole machines of' this type.

25 indicates a buttonhole cutter pivotally mounted to the frame at 26and which is actuated from the cani 19 at the proper vtime to cut thebuttonhole.

I have above referred briefly to some of vthe essential parts of abuttonhole sewing machine of the type above mentioned, and beforeentering into a description of my im-` provements, I will recite brieflythe sequence of operationsperformed in stitching a buttonliole.

Then the machine is at rest, the needle 5 and work clamp 3 are bothraised and the Work-holding means is so positioned that the Work wsupported thereby will be Vplaced properly to have the buttonhole cuttherein Aby the cutter 25, this being referred to as vshaft 24 is set inoperation to actuate the stitch-forming mechanism to cause it toyproduce a series of stitch-forming movements which form the edgestitches on 'the cut buttonhole. During the stitching operation thework-holding means is given a slow feeding movement first in onedirection and then in the other to cause the stitches to 'be formed downone side of the buttonhole -and lthen bacli along the other side, the

stitch-forming mechanism being rotated at the ends of the buttonhole so'that the stitches Will'be properly formed around the buttonhole end.When the stitchingfon theV buttonhole is completed, the shaft p24 isbrought to rest automatically by a suitable stop motion, the work clamps3 are raised, l

and the Work-holding means is given a'quick movement to the right, Fig.1, to bring it from stitching to buttonhole-cutting position again, atwhich time the machine comes4 to rest.

The shaft 24 is driven from a driving belt,

and said shaft is started in operation or,

brought to lrest by shifting the belt either onto the pulley 39 which isfast on the shaft, or onto the pulley 40 Which is loose on the shaft.The shifting of the belt is accomplished by a belt shifter 41 carried bya belt-shifting rod 42. When the belt is shifted onto the loose pulley40, 'the machine is brought to rest with the needle raised by means of astop motion which is herein shown as comprising a stop cam 43 fast onthe shaft 24, and a stop member44 which is yieldingly carried by an arm-45 fast on the application, Se.

is va division,

cani with the stop member 44 will produce,

a braking effect, and when the stop cam has been turned into theposition shown `in Fig. 1 so that the notch 47 therein comes in linewith the end 48 of the member 44, said end will drop into the.notchtherebypositively stopping the shaft 24.

The machine herein shown is provided with means for seizing and grippingthe under thread at the end fof the stitching operation and also meansfor severing lthe under thread betweenthe holding means and the work.The means for seizing and holding theunder thread is similar to thatillustrated and described in my co-pending No. 206,215 filed December ofwhich and is in the form of acurved arm 27 fast on a rock-shaft 29mounted in bearings in a bracket 30 carried by the turret, said armhaving a hook 2R at the end thereof. The arm 27 is normally held .in the`position shown in Fig. 6 and the rock-shaft 29 has an arm 82thereon-.situated to be engaged by a lever or arm 33 pivoted at 34 tothe frame and actedl upon by a spring 35 which norniallyliolds -itagainst the stop 37.

In the operationy of the machine after the i stitch-forming mechanismhas been brought to rest yand while the work is being carried fromstitching to buttonhole-cut'ting -position the turret is turningclockwise, Fig. 6, during which movement the arm 32 will engage thearmor lever 33, and as the arm 32 is wiping past the arml, the hook 27will be swung to the left'Fig. G. lVhen*v the arm 32 passes oiffrom thearm 33, the hook will be returned to the position shown in Fig. G. iDuring this swinging movement of the hook 28 it-engages the under threadand draws the latter to one side against the y,

under face of the throat -platejl'i l.The machine herein shown is alsopro'i-'ided with means for cutting the under thread close to the Workafter it has been clamped to the throat-plate 13. Such thread-cuttingmechanism is similar to that illustrated and described in myabove-mentioned co-pending application Se. No. 206,215.l filed December8, 1917, .and comprises two levers 51, pivotally mounted on two studs53` to shift the belt onto the loose' the present applicationl held bythe looper 1() and 540, respectively, that are carried by.a plate 55whichy is removably secured. to the clamp plate 1 by means of screws 56.The lever 51 carriesy at lits end .a cutting block 57 and the lever 52carries at its 'end a knife 530, said knife and cuttngblock op-v eratingin' close proximity to the upper face of the clamp plate` 1. Theopposite ends of the levers are connected by a fspring 54 which tendsvto separate the operative ends from each-other. levers is a toggledevice comprising two toggle members 58, 59 pivotally connected block.Means are provided for thus straightening the toggle levenafter the.

stitching operation is completed and while Situated between ythe i thework is being carried from stitching to Abuttonhole-cutting position.Such means comprises a lever 63 pivoted at 64 to the plate 55 andconnected atone end to the stud 6() of the toggle device, the other end66 of the lever projecting beyond the clamp plate and operating in arecess 67 formed in the controlling' member 68"that is car-y ried bythe' bed-plate2 of the machine. AThe recess 67 lis so positioned and ofsuch dimensions that during the movement of the clamp plate rl fromstitching to buttonholecutting position, theend be brought` against the.shoulder G9 ofy the recess thereby turning `the lever and straighteningthe toggle device. l1`he under thread will thus be cut close to the workduring the -movement ofthe clamp plate fromv stitching tobuttonhole-cutting position.

` In the ordinary operation of a sewing machine of this type the upper'needle carries a'loop of upper thread t through the work andthrough aloop of under thread at each penetrating thrust and. the looper 10 isactuatedv to engage each loop 'of 'upper threadvafter it 'has' beencarried through the work. and through the loop of under raised..` Hencewhen a sewing machine of this type: is brought to rest with the needle5, raised, a loop of under tliread will be cut beneath the work bythreatwutting mechanism. such as above 'described` a short length` ofthread will be produced which 6G ofthe lever will and if the thread isconstitutes the loop of upper thread. One Such short length will resultfrom each buttonhole and after the machine has been in operation forsometime the accumulation of these short lengths is apt tol clog up andn interferev with `the operation of the lunder thread mechanism.

It is the object of my present invention to provide means for preventingthe looper from engaging the'loop of upper thread during the laststitch-forming movement, so that when the machine is brought to restthere will be no loop of upper thread held v by the looper. Y Conseuently, the operation ing a roll 77 which operates'in a cam slot 78formed in a member 79 that 4is connected to the looper, and that duringthe stitching operation the vertical reciprocations of-'thel spindle 20occur at such intervals as to cause the looper to properly entereach'loop ofupper thread. This operation i's illustrated diagrammatically in'Fig. 7l -wherein the needle 5 is illustrated as being withdrawn from thework, thus to throw out thel loop t of upper thread and lthe point ofthe looper 10 is illustrated as just enteringthe loop t.

t of upper thread.l I propose to secure this To cause kthe looper tomissthe loop during the last stitch-forming movement, the

movement of the spindle 20 is retarded so that the forward movement ofthe looper will not occur until after the needle l5. has been raised tosuch a point as to'lift theloop t of upper thread above the looper. If,for instance, when the needle is in the position shown in Fig. 7, thelooper 10 is retracted to occupy the position shown in Fig. 8, thenbythe time the looperreaches the point of the needle, the latter will beelevated into the position shown in Fig. 9, in which position the'eye ofthe needle is above the looper and the looper will, therefore, miss theloop retardi'ng or`retracting Imovement of the looper by meanscontrolledlb'y the stop'motion lso that just when the machine is comingto rest and the needle 5 is being raised during the last stitch-formingmovement,

.- l the looper will receive its retarding or retracting movement andwill thus skip lthe last stitch. The lever 21 by which the spindle 20is, given its vertical reciprocation is pivotally mounted on a pivotalpin 22 carried by the frame 12. The ends 8() of this pivotal pin whichis journaled in the plate.

retarding A' frame 12 are eccentrically situated, and as a result, ifthe pivotall pin 22 is turned about its ends 80 asA an axis, the lever21 will be raised or lowered, and since the rear 'end of the lever isconnected tov the rod 23', such raising or lowering will be effective atthe front end where it is connected to the spin dle 20. One of the ends80 has an arm 8l fast thereon which is connected to the lower end of arod 82 that extends up through the bed plate and is connected at itsupperl end toa lever 83 fast on a rock-shaft 84 that is journaled in abracket 85 carried by the bed Said rock-shaft has an arm 86 fast thereonwhich is situated in position to be engaged by a finger 87 extendingfrom the stop member 44 when said stop memberis being depressed b thestop cam. Hence, when the stop motion is set in operation to bring themachine to rest and the'stop cam is acting on the stop member 44, thedownward swinging movement of the latter will rock the lever 83 therebyraising the .rod 82 and turning the pin 22. Thiswill raise .the lever 21and consequently raise the spindle 20 slightly, such movementv operatingto retract or rethe eccentric portion of tard the looper relative to theupper needle.

In other words, during the last stitch-form- -ing movement the looper isthrown out of timewith.` the other elements of the stitch-- formingmechanism and the looper is thus caused to miss or skip the loop ,t ofthe upper thread. Hence when .the cutter is actuated there will be onlythe under thread and stay-cord leading from the under side of the work,both of which will be cut .close to the work. 'When thestitching'operation is started-on the next buttonhole the looper isautomatically returned to its' normal positionin proper timed relationwith the up.

per needle because the startingof the stitch ing operation` involvesshifting the actuator rod 42 to carry the belt onto thefast pulley, andthis movement of lthe actuator rod carries rthe arm 87 laterally out ofengagement with the arm 86. The rod 82 is acted g.

upon by'a springlOO which tends to force it downwardly, and, therefore,as soon as the arm 83 has been released from its en'f gagement with thearm 87, the spring 100 will return the looper to its proper position.v

'last loop of upper thread, and while I have illustrated herein aselected embodiment of my invention, I do not wish t'o be limited to theconstruction'al features shown.

The means herein shown for holding and gripping the under thread and forsevering it close to the work are not claimed herein as they form thesubject matter of my abovementioned co-pending application Se. No.206,215, of which this is a division.

isesae I claim:

l. In a sewing machine, the combination with work-holding means, ofstitch-forming mechanism comprising upper-threadhandling mechanism andunder-thread-handling mechanism, means to givel said stitchformingmechanisma series of stitch-forming movements and then bring it to rest,means to prevent the interlocking of the upper and under threads duringthe last'stitchforming Imovement, and means to cut the under threadbeneath the work at pletion of the stitching operation.

2. In a sewing machine, the combination with work-holding means, ofstitch-forming mechanism comprising upper-threadhandling mechanism andunder-thread-handling mechanism, the latter havin provision fordelivering a stay-cord to tie work as the stitches are formed, means togive said stitch-forming mechanism a series of stitch-forming movementsand then bring it to rest, means to prevent the interlocking of theupper and under threads during the last stitch-forming movements of theseand means to cut the under thread and stay cord beneaththe work at thecompletion of the stitching operation.

3. In a sewing machine, the combination with work-holding means, ofstitch-forming mechanism comprising upper threadhandling mechanism andunder-thread-handling mechanism, means -to give said stitchformingmechanism a series of stitch-forming movements and then bring it torest,l means to prevent the interlocking of the up-` per and underthreads during the last stitchforming movement, and a device on' thework-holding means to cut the under thread beneath the work at thecompletion of the stitching operation.

Li. In a sewing machine, the combination with work-holding meansincluding a clamp plate for supporting the work and .work clampsto clampthe work thereagainst, of stitch-forming mechanism comprising'upper-thread-handling mechanism and underthread-handling mechanism,means to give said stitch-formingmechanism a series of stitch-formingmovements and then bring it to rest, means to prevent the interlockingof the upper and under threads during the last stitch-forming'movementof the series,.and means carried by the -clamp plate to cut the underthread beneath the work.

5. In a sewing machine, the combination with work-holding meansyincluding a clamp `plate for supporting the work and workI ing.provision for delivering a stay-cord to the work as the Istitches areformed, means to give said stitch-forming mechanism a the comseries ofstitch-forming movements and then bring it to rest, means to prevent theinterlocking of the upper and under threads during the laststitch-forming movement of the series, and means carried by the clampplate to cut the under thread and stay-cord beneath the work at the endofthe stitching operation.

v6. In a sewing machine, the combination with work-holding means, ofstitch-forming mechanism comprising upper threadhandling mechanism andunder-thread-handling mechanism, means to give said stitchformingmechanism a series of stitch-forming movements and then bring it torest, meansl for producing a relative movement between the work-holdingmeans and stitchforming mechanism. both during the stitchformingmovements and after the stitchforming mechanism has been brought torest, means 'to prevent the interlocking of the upper and under threadsduring the last stitch-forming movement of the series, and

vupper and under threads and including loop-engaging means beneath the.work for engaging the loops'of upper thread, means to give saidstitch-forming mechanism a series of-stitch-forming movements, means torender the loop-engaging means inoperative during the laststltch-forming movement of the series, and means to cut the under threadbeneath4 the work at the end' of the stitching operation.v

8. In a sewing machine, the combination with work-holding means, ofstitch-forming mechanism `constructed to concatenate upper and underthreadsv and including loop-engaging means beneath the work for engagingthe loops o upper thread, means to give said stitch-forming mechanism aseries of stitch-forming movements, means to render `the loop-engagingmeans inoperative during the last stitch-forming movement of the series,and means carried by the Workholding means to cut' the under threadbeneath the work at the endV of the stitching operation.

9. In a sewing machine, the combination j with work-holding` means, ofstitch-forming mechanism constructed to concatenate loops of upper andunder threads and comprising a needle to insert loops of needle threadthrough the work, and a looper operating beneath the work to. take theloops of needle thread as they are inserted through thework, -means togive said mechanism a series of stitch iforming movements, and means toretard the action of said looper relative to that of the needle duringthe last stitch-forming movement of the series so withWork-holdingmeans, of stitch-forming'` mechanism constructed toconcatenate loops of upper and under threads and comprising a needle toinsert loops of needle thread through the Work and a looper operatingIbeneath the work to take the loops of needle thread as they are insertedthrough the work, means to give said mechanism a series ofstitch-forming movements, a stop motion to bring the stitch-formingmechanism to rest at the end of the stitch-forming movements, and meansactuated by the stop motion to prevent the interlocking of the upper andunder threads during the last stitch-forming movement of the series.

ll. In a sewing machine, the combination with Work-holding means, ofstitch-forming mechanism constructed to concatenate loops of upper andunder threads and comprising a needle to insert loops of needle threadthrough the work and a looper operating beneath the Work to take theloops of needle thread as they are inserted through the work, means togive said mechanism a series of stitch-forming movements, a stop motionto bring lthe stitch-forn'ling mechanism to rest at the end of thestitch-forming movements, and means actuated by said stop motion toretard the action ofthe looper during the last stitch-forming movementthereby to prevent it from engaging the loop of upper thread.

l2. In a sewing machine, the combination with Work-holding means,-ofstitch-forming mechanism constructed to concatenate loops loops of upperthread, means to give said mechanism a series of stitch-formingmovements, means to retard the `action of said loop-engaging-meansduring the last stitchforming movement of the series so as to cause itto fail to engage the loop of upper thread, and means to cut the underthread beneath the Work at the end of the stitching operation.

13. In a sewing machine, the combination stitch-forming mechanism torest at the end of the stitch forming movements, yand means actuated bythe stop motion to prevent the interlocking of the upper and'unvderthreads during the last stitch-forming 'movements of the seriesand meansto cut the under thread beneath the work at the end of the stitchingoperation.

14. In a sewing machine, the combination with Work-holding means, ofstitch-forming mechanism arranged to concatenate loops of upper andunder threads and `comprising loop-engagmg means beneath the Work toengage the loops of upper thread, means including a stop motion to givevsaid mechanism a seriesot stitch-forming movements and then to bring itto rest, means .actuated bysaid stop motion to retard the action of theloop-engaging means during the last stitclrforming movement rthereby toprevent it from engaging the loop of upper thread, and means to cut theunder thread beneath the Workat the end of the stitching operation.'

,In testimony whereof, I have signed my name to this specification. I

FRANK ZALESKL

